Method of generating working steam



Nov. 1, 1932. w. ABENDROTH ET AL METHOD OF GENERATING WORKING STEAM Filed Feb. 5, 1926 Patentred Nov. l, 1932 PATENT OFFICE `AB unimo'isii,,or :BEnLrN-cHAnLo'rrENBUnG, ArmfrrANs GLEICHMANN, 0F

BERLIN-SIEIIIENSSTADT, GERMANY, ASSIGNORS TO SIEMENS-SOHUCKERTWERKE '.GESELLSGHAFT"MIT BESCHRANKTER HAFTUNG, OF SIEMENSSTADT, GERMANY, A

l" I a. GERMAN conronn'rron ffiin'rnon or GnNERATINc-x- WORKING STEAM Appiiafioa medrebruary 5, 1926, serial no. 86,216, and in Germany February 5, 1925.

. 1f Our invention `relates'to a systemfor the production and use ofi high pressure steam, especially steairn'whiclr isl produced: in the 4, neighborhood of the criticalV point;V

ffl "It is possible tolproduce steam without the A occurrence ofthe' so-called'ebullition phenomenon,A `byfforcingV the working medium tlrrou'glrfa heated pipeV system positively by means ofI` i a pump, `operating ati `a pressure which is substantially equalto the critical y pressure, and heating .y thef working `medium y at least to thecritical" temperature. In this v process vapor and fluidl of equal pressure and equaltemperature, but of different physical '1.rI'o'per'ties,` cannot simultaneously exist together, but the entire Vmass of liquid'which s has reached the critical temperature at the critical Ipressure is converted directly into steam.` That is to say, theproduction of i steam occurswithout the absorption of latent Y heat.`

Since thepressure ofthe steam produced VVin this Way is very high, the design of steam engines capable ofoperating over the entire pressure range fromithe high pressure to ,the condenservpressure, involves great diiliculties.V VIt-has therefore beenproposed to `throttlethe 'steam' thus produced downto the working pressure, :and for Vthis purpose the use of a pressure reduction valve'has been vsuggested. Since,lhowever, the throttling Vin f "a pressure reduction valve occurs without the y Aequivalentjof a mechanical load, itis prefer- `ahlen-to use for this "purpose a special auxil- .iarymachine in which'A the drop in pressure canbemadeuseful. f p s f In plants of thisnature itis necessary to im-part to the waterto'be evaporated, from -vthe'very beginning, that pressure which it should Yhave in the heater when vbeing converted into steam, `a pressure which is thus "higher than the "critical pressure.V The feed pump, necessary forl this. purpose or other i similar devices, must adapt themselves very accurately to the prevailing steam consumption since the steam generator pipes have no Astorage capacity which canlserve for equal- A' izing theiiuctuations in steam consumption. Above all provisions `must be'm'ade that at "a sudden extra consumption `of steam 'the .auxiliary steam engine.

pressure cannot drop appreciably below the critical pressure.` Onthe other hand it must beV prevented that when the. consumption of the steam fallsl suddenly excessively high pressures (or other operatingl difficulties) develop.V By utilizing thepressure ldiiference existing between the high pressure and working pressure side of the system, for driving the feed pump, it is possible to `adapt the output ofthe feed pump automatically and withina Wide range to the prevailing steam consumption in such a manner that the i necessary pressure is-always maintained in the rst stage of the steam generator.

Nhen the output and the steam consumption of the main steam consumerewhich may in the present case be a steam turbine with its conventional i governing equipment-rises, the circulation. of the Working medium is accelerated and thereby also raises the output of the feed pump `which is operated by the H A condition may occur where the output of the auxiliary steam engine, such as a turbine, does not perfectly adapt itself to the pump output to be covered. In such a case our invention provides aneiiicient remedy. i 1

According to our invention an electric ma* chine is provided for the equalization or balancing of the outputs between the auxiliary steain engine and the pump, which :machine drives the feed pump in parallel with the auxiliary `engine at a suitable ratio, for instance directly as shown. This electric machine is connected with the same network'as the main generator. Its speednis so proportioned that at normal operation it runs idle and thus neither consumes nor supplies power-.- "Since the feed pump is required to supply more liquid working medium to the steam generator at increased load, in orderto im-` mediately replenish the increased amount of steam drawn from the generator, the auxiliary throttling machine as a consequence must carrya heavier loadput Von it through the increased pump load. This would tend toV reduce the speed of the auxiliary machine -and thusV also the speed of the dynamo electric machine coupledwith it to tend to decrease so that the latter now commences to the valve opens, further, a larger volume of steam passes through the turbine 4 and the )drop of pressure is thereby compensated, y while when the consumption of steam drops v,and the flow through the valve 10 is reduced, the pressure'behind the turbine 4 is reduced t thereby to the requiredvalue, i. e. the turi bine 4 operates with variable back pressure pj and consequently witliiuctuating output, the

uctuations in output being balanced by the `dynamo electric machine.

Various fmodiications and changes may fbemade without departing from the spirit l "and scope of our invention and we desire,

therefore, that only such limitations be placed upon it as are justified by the state of theprior art.

`We claim as our invention zr l. In a speed flow vapor power plant in `combination a tube system constituting the vapor generator, a centrifugal pump for `forcing a liquid working medium in a coiitinuous stream through said system, means i for heating the liquid in 'a portion of said sys- A tem to generate vapor at high d pressure, amain prim-e mover operating at a vapor pressure lower than the generating pressure, and

means for reducing the pressureof the genf Y erated vapor to the pressure required for the i 2.30:

main prime mover, Asaid reducing means comprising an auxiliary prime Vmover operated by saidV vapor and connected in the supply line` to said main prime mover and acting as a vapor throttling element` said auxiliary prime mover operating said pump, and an electric equalizing machine connected to an electric power line and connected in fixed relation to said auxiliary prime mover and said pump, and operating as a motor when the 1 delivered auxiliary `prime mover powei is below therequired pump power, and operating` ,as a.' generator when the delivered prime mover power is above the required pump power, whereby said auxiliary prime mover acts as a vapor throttling element,'and the pump output varies substantially with the I amount of vapor produced by said generator.

p 2. Infaspeed Vflow vapor power plant in combination a ,tube system constituting the ,vapor generator, a centrifugal pump for forcing a liquid working medium in a continuous stream through said system, means f i for heating-the liquidv in a portion of said Y' @rated vapor to the pressure required for said Y i system to generate vapor at high pressure, a

main prime mover operating at a vapor presi sure lower than the generating pressure, and

means for reducing'tlie pressure of the gen main prime mover, said reducing means comprising an auxiliary prime mover, directly connectedpto the delivery side of said generator, and adapted to pass through it the entire amount of vapor produced in said gen- `erator, and acting as a vapor throttling element,said auxiliary prime mover operating Lares. u `WILHELM ABENDROTH.

HANS GLEICHMANN. 

